Assessment of the bone status of Nigerian women by ultrasound and biochemical markers

Risk factors for osteoporosis among postmenopausal women in a Nigerian teaching hospital

Background

Osteoporosis is a progressive bone disease characterized by a reduction in bone mass and density, leading to bone fragility and an increased risk of sustaining fractures. Several studies have shown that the risk for osteoporosis increases with age and after menopause.

Methods

A cross-sectional study was undertaken of 422 postmenopausal women at the Family Medicine Clinic of the Lagos State University Teaching Hospital (LASUTH). Variables such as socio-demographic characteristics, anthropometric indices, and lifestyle habits of participants were assessed. In addition, bone mineral density was measured using a validated portable dual-energy X-ray absorptiometry scanner. The results of the bone mineral density were analyzed based on T-scores.

Results

The mean age of the study subjects was 59.8± ±6.4 years, while the mean age at menopause was 50.15 ± 4.1 years. The majority of the subjects were obese (41.5%), while the prevalence of osteoporosis and osteopenia was 15.1% and 30.6%, respectively. The use of oral steroids was associated with osteoporosis (P < 0.05).

Conclusion

We recommend regular bone mineral density screening of postmenopausal women at the primary care level for early diagnosis and treatment of osteoporosis to prevent fragility fractures.

Longitudinal Change in Bone Density, Geometry, and Estimated Bone Strength in Older Men and Women From The Gambia: Findings From the Gambian Bone and Muscle Aging Study (GamBAS)

Musculoskeletal aging in the most resource-limited countries has not been quantified, and longitudinal data are urgently needed to inform policy. The aim of this prospective study was to describe musculoskeletal aging in Gambian adults. A total of 488 participants were recruited stratified by sex and 5-year age band (aged 40 years and older); 386 attended follow-up 1.7 years later. Outcomes were dual-energy X-ray absorptiometry (DXA) (n = 383) total hip areal bone mineral density (aBMD), bone mineral content (BMC), bone area (BA); peripheral quantitative computed tomography (pQCT) diaphyseal and epiphyseal radius and tibia (n = 313) total volumetric BMD (vBMD), trabecular vBMD, estimated bone strength indices (BSIc), cross-sectional area (CSA), BMC, and cortical vBMD. Mean annualized percentage change in bone outcomes was assessed in 10-year age bands and linear trends for age assessed. Bone turnover markers, parathyroid hormone (PTH), and 25-hydroxyvitamin D (25(OH)D) were explored as predictors of change in bone. Bone loss was observed at all sites, with an annual loss of total hip aBMD of 1.2% in women after age 50 years and in men at age 70 years plus. Greater loss in vBMD and BSIc was found at the radius in both men and women; strength was reduced by 4% per year in women and 3% per year in men (p trend 0.02, 0.03, respectively). At cortical sites, reductions in BMC, CSA, and vBMD were observed, being greatest in BMC in women, between 1.4% and 2.0% per annum. Higher CTX and PINP predicted greater loss of trabecular vBMD in women and BMC in men at the radius, and higher 25(OH)D with less loss of tibial trabecular vBMD and CSA in women. The magnitude of bone loss was like those reported in countries where fragility fracture rates are much higher. Given the predicted rise in fracture rates in resource-poor countries such as The Gambia, these data provide important insights into musculoskeletal health in this population. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Atherogenic Index of Plasma and Anthropometric Measurements among Osteoporotic Postmenopausal Sudanese Women: Possible Risk for Cardiovascular Disease

Introduction

Data examining the health of menopausal women and the prevalence of osteoporosis remain to be limited in Africa, especially in sub-Saharan countries. Thus, in this current study, we aimed to assess the atherogenic index of plasma (AIP) and anthropometric measurements of osteoporotic postmenopausal women and determine their risk for cardiovascular disease (CVD).

Methods

This is a cross-sectional, community-based study. Postmenopausal women (n = 300), aged ≥45 years, were recruited from Khartoum state, Sudan. Dual-energy X-ray absorptiometry was used to assess bone density. Weight, height, and waist circumference were measured twice. Fasting blood samples (5 ml) were collected to determine total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). AIP was calculated as an indicator of CVD risk.

Results

The mean age of the postmenopausal women was 61.6 ± 10.2 years (range 47–90 years). Women (n = 80) had the normal T-score, and an equal number had osteoporosis (n = 110) and osteopenia (n = 110). The prevalence of osteoporosis was 36.7%. Many postmenopausal women with normal T-scores suffered from general (71.2%) and central (94%) obesity. Postmenopausal women had high TC (24.4%), TG (25.6%), LDL-C (13.7%), and low HDL-C (76.0%) levels. Osteoporotic women (36.4%) were found to have a medium to high risk of CVD as determined by AIP. Women with normal T-scores had a higher number of CVD risk factors. A positive correlation was noted between AIP and TC among osteopenic (r = 0.292; P=0.002) and osteoporotic women (r = 0.265; P < 0.001).

Conclusion

Osteoporosis was prevalent among Sudanese postmenopausal women who also had an increased risk for CVD. Public health education about osteoporosis and CVD risk is thus recommended.

Osteoporosis, Rather Than Sarcopenia, Is the Predominant Musculoskeletal Disease in a Rural South African Community Where Human Immunodeficiency Virus Prevalence Is High: A Cross-Sectional Study

The rollout of antiretroviral therapy globally has increased life expectancy across Southern Africa, where 20.6 million people now live with human immunodeficiency virus (HIV). We aimed to determine the prevalence of age-related osteoporosis and sarcopenia, and investigate the association between HIV, bone mineral density (BMD), muscle strength and lean mass, and gait speed. A cross-sectional community-based study of individuals aged 20-80 years in rural South Africa collected demographic and clinical data, including HIV status, grip strength, gait speed, body composition, and BMD. Sarcopenia was defined by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) guidelines, and osteoporosis as BMD T-score ≤ -2.5 (if age ≥50 years). The mean ± standard deviation (SD) age of 805 black South African participants was 44.6 ± 14.8 years, 547 (68.2%) were female; 34 (13.2%) were men, and 129 (23.6%) women had HIV, with 88% overall taking anti-retroviral therapy. A femoral neck T-score ≤ -2.5, seen in four of 95 (4.2%) men and 39 of 201 (19.4%) women age ≥50 years, was more common in women with than without HIV (13/35 [37.1%] versus 26/166 [15.7%]; p = 0.003). Although no participant had confirmed sarcopenia, probable sarcopenia affected more men than women (30/258 [11.6%] versus 24/547 [4.4%]; p = .001]. Although appendicular lean mass (ALM)/height2 index was lower in both men and women with HIV, there were no differences in grip strength, gait speed, or probable sarcopenia by HIV status. Older age, female sex, lower ALM/height2 index, slower gait speed, and HIV infection were all independently associated with lower femoral neck BMD. In conclusion, osteoporosis rather than sarcopenia is the common musculoskeletal disease of aging in rural South Africa; older women with HIV may experience greater bone losses than women without HIV. Findings raise concerns over future fracture risk in Southern Africa, where HIV clinics should consider routine bone health assessment, particularly in aging women. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

A call to action for osteoporosis research in sub-saharan Africa

Data abounds on osteoporosis in developed countries unlike developing countries, particularly those in sub-Saharan Africa. This review was done to confirm the paucity of data the authors suspected and to encourage studies in this field. AJOL (African Journals Online), MEDLINE and EMBASE databases were searched for studies published from January 1980 to August 2018. The eligibility criteria for inclusion were observational studies evaluating osteoporosis prevalence or incidence rates of fragility fractures. Out of 1,170 articles identified, six met the eligibility criteria. Prevalence of osteoporosis ranged from 18.2% to 65.8% across a heterogenous at-risk population. Bone mineral density assessment was limited by the measurement method, with most studies using quantitative ultrasound instead of standard bone densitometry.

From the available studies, the prevalence of osteoporosis and fragility fracture incidence may not be low in Sub-Saharan Africa; what is, however, evident is the paucity of good quality data from this region. Considering an expected aging population in sub-Saharan Africa, future research should be encouraged and aimed at clarifying the burden of this non-communicable disease. This will guide healthcare policy in this medically underserved part of Africa.

Osteoporosis in Africa-where are we now

Africa is experiencing an exponential increase in the number of older persons. The number of persons surviving with human immunodeficiency virus is simultaneously increasing due to improved availability of anti-retroviral therapy. The burden of non-communicable diseases, in particular, osteoporosis and its consequent fragility fractures, is also predicted to increase. Osteoporosis, however, remains a neglected disease and there are no age-standardized reference data available to accurately screen and diagnose individuals with osteoporosis. Epidemiological studies reporting the incidence of hip fracture or vertebral fractures are limited from Africa, especially Sub-Saharan Africa. The studies are usually limited as they are based on a retrospective data and small study numbers and often from a single study site. However, compared with early initial studies, the more recent studies show that osteoporosis and fractures are increasing across the continent. The overall incidence rates for osteoporosis and fractures still vary greatly between different regions in Africa and ethnic groups. Predisposing factors are similar with those in developed countries, but awareness of osteoporosis is sorely lacking. There is a lack of awareness among the population as well as health authorities, making it extremely difficult to quantify the burden of disease. There is great potential for research into the need and availability of preventive strategies. The FRAX® tool needs to be developed for African populations and may circumvent the shortage of bone densitometry.

Bone mineral density in an urban and a rural children population-A comparative, population-based study in Enugu State, Nigeria

INTRODUCTION

Osteoporosis is one of the non-communicable diseases linked to urbanisation. The foundation of osteoporotic fractures stems from childhood. Therefore, studies that promote maximising peak bone mass are strongly advocated. Studies have shown that there are differences in the incidence of osteoporotic fractures in rural and urban communities. No study has investigated urban-rural differences in BMD of Nigerian children. This study, therefore, aimed to investigate urban-rural differences in BMD of Nigerian children and the association with physical activity, demographic and anthropometric variables.

METHODS

In a cross-sectional, study in Enugu, Nigeria, estimated bone mineral density (eBMD) was measured at the calcaneum using the QUS densitometer, Hologic Sahara, in 457 urban (Enugu metropolis) and 559 rural (Nsukka community) children aged 6-14 years. Height, weight and physical activity were measured. Independent sample t-test was used for comparative analysis while Pearson correlation coefficients and multiple regression models were used to examine the relationship between the eBMD and the other parameters.

RESULTS

The mean (S.D) eBMD of the urban children [0.52(0.09) g/cm²] were significantly higher (p < 0.05) than their age- and gender-matched counterparts in the rural areas [0.51(0.08) g/cm²]. Age and weight predicted (p < 0.05) the eBMD in the urban subjects while only age was the predictor (p < 0.05) in the rural subjects. The physical activity pattern had no relationship with eBMD in both urban and rural children in Enugu, Nigeria.

CONCLUSIONS

The eBMD of rural children is lower than that of their age- and gender-matched urban counterparts.

Bone mineral density in people living with HIV: a narrative review of the literature

Bone health status is largely absent in South Africa, the main reasons being the absence and cost-effectiveness of specific screening equipment for assessing bone mineral density (BMD). Various risk factors seem to play a role, some of which can be modified to change bone health status. Urbanisation is also a public health concern. Changing nutritional, as well as social behaviour, play integral roles in the prevalence and incidence of decreased BMD. Furthermore, human immunodeficiency virus (HIV) specifically, has a negative impact on BMD and although highly active antiretroviral therapy increases the prognosis for HIV-infected individuals, BMD still seem to decrease further. Dual energy X-ray absorptiometry is considered the gold standard for BMD assessment; however, recent developments have provided more cost-effective screening methods, among which heel quantitative ultrasound appears to be the most widely used in resource limited countries such as South Africa.

Reduced quantitative ultrasound bone mineral density in HIV-infected patients on antiretroviral therapy in Senegal

BACKGROUND

Bone status in HIV-infected patients on antiretroviral treatment (ART) is poorly documented in resource-limited settings. We compared bone mineral density between HIV-infected patients and control subjects from Dakar, Senegal.

METHODS

A total of 207 (134 women and 73 men) HIV-infected patients from an observational cohort in Dakar (ANRS 1215) and 207 age- and sex-matched controls from the general population were enrolled. Bone mineral density was assessed by quantitative ultrasound (QUS) at the calcaneus, an alternative to the reference method (i.e. dual X-absorptiometry), often not available in resource-limited countries.

RESULTS

Mean age was 47.0 (±8.5) years. Patients had received ART for a median duration of 8.8 years; 45% received a protease inhibitor and 27% tenofovir; 84% had undetectable viral load. Patients had lower body mass index (BMI) than controls (23 versus 26 kg/m(2), P<0.001). In unadjusted analysis, QUS bone mineral density was lower in HIV-infected patients than in controls (difference: -0.36 standard deviation, 95% confidence interval (CI): -0.59;-0.12, P = 0.003). Adjusting for BMI, physical activity, smoking and calcium intake attenuated the difference (-0.27, CI: -0.53;-0.002, P = 0.05). Differences in BMI between patients and controls explained a third of the difference in QUS bone mineral density. Among patients, BMI was independently associated with QUS bone mineral density (P<0.001). An association between undetectable viral load and QUS bone density was also suggested (β = 0.48, CI: 0.02;0.93; P = 0.04). No association between protease inhibitor or tenofovir use and QUS bone mineral density was found.

CONCLUSION

Senegalese HIV-infected patients had reduced QUS bone mineral density in comparison with control subjects, in part related to their lower BMI. Further investigation is needed to clarify the clinical significance of these observations.

Genetic and environmental factors in human osteoporosis from Sub-Saharan to Mediterranean areas

The aim of this study was to determine the prevalence of known gene polymorphisms associated with osteoporosis in postmenopausal normal women from Burkina Faso and Sicily, compared to postmenopausal Sicilian women with osteoporosis, and to establish the weight of environmental factors in the mechanism of osteoporosis. Bone mass density (BMD) was measured by phalangeal quantitative ultrasound (QUS) in Burkinabe woman and by the dual X-ray absorptiometry at the femoral neck in Sicilian women. The polymorphisms of the vitamin D receptor (VDR) gene, estrogen receptor (ESR) gene, calcitonin receptor (CTR) gene and COL1A1 collagen gene were characterized by PCR. The social characteristics of studied women were evaluated by a specific questionnaire. The observed percentages of single specific polymorphisms did not differ from that expected with exception of VDR B allele and ESR X and P allele in Burkinabe and Sicilian women, respectively. Association analyses and multivariate two-step regression model of social and molecular parameters, demonstrated that in comparison to the VDR, ESR, CTR polymorphisms, physical activities and healthy diet, associated with outdoor work are the best favourable prognostic factors for osteoporosis. A diet rich in calcium, other minerals and vitamin D in association with physical activity represents the most effective way to maintain not only a healthy bone structure but also an acceptable BMD. This is particularly true for Sub-Saharan women.

Differences in bone size and bone mass between black and white 10-year-old South African children

INTRODUCTION

Black and white South Africans hail from vastly disparate cultural and socio-economic backgrounds the result of which exposes black children to numerous factors known to impact negatively on bone mass. Thus, we studied ethnic differences in bone size and bone mass between 476 10-year-old black and white South African girls and boys (black boys n=182, white boys n=72, black girls n=158, white girls n=64) who formed part of a longitudinal cohort of children born in Johannesburg, South Africa, during 1990.

METHODS

Bone area (BA) and bone mineral content (BMC) were measured at the whole body, total hip, femoral neck, lumbar spine (L1-L4) and mid- and distal radii by dual energy X-ray absorptiometry (DXA). Vertebral heights and metacarpal indices were measured. Anthropometry, skeletal maturity and pubertal development were also assessed.

RESULTS

After correction for height, weight, gender and puberty, black children had greater BMC at the femoral neck (P<0.0001), total hip (P<0.05) and mid-radius (P<0.001) than white children.. At the whole body, lumbar spine, and distal one-third of the radius, there were no differences in BMC between black and white children after correction for differences in body size. After correction for height and puberty, vertebral heights were less in black children than white children, and cortical areas at the second metacarpal were greater in black children.

CONCLUSION

These findings suggest that, at the femoral neck, total hip and mid-radius, these differences are not a result of differences in anthropometry, bone age or pubertal stage, or environmental factors but are most likely to result from genetic differences.

Effect of Norplant contraceptive on the bones of Nigerian women as assessed by quantitative ultrasound and serum markers of bone turnover

Levonorgestrel is a commonly used progestin-only contraceptive that is available as subdermal (Norplant) and intrauterine implants. Other progestin-only contraceptives such as injectable medroxyprogeterone acetate have been shown to decrease bone mineral density in long-term users. We used calcaneal ultrasound to compare the bone quality of Nigerian women between 25 and 50 years of age who had Norplant implants for 1-4 years to that of women who were not using any form of hormonal contraceptive. The mean stiffness index of women who had Norplant implants for as long as 4 years was not significantly different from that of controls. However, serum markers of bone turnover were significantly decreased in women with Norplant implants compared to age-matched controls. Serum bone-specific alkaline phosphatase was significantly decreased in subjects with Norplant implants for 1 year (13.7+/-6.0 vs. 23.0 U/L for controls, p = .001) and serum NTx was significantly decreased in subjects with implants for 3 years (10.6+/-4.9 vs. 17.6+/-7.7 bone collagen equivalents per liter for controls, p < .001). We conclude that although levonorgestrel contraceptive decreased overall bone turnover, it had no deleterious effect on the bone quality of women using Norplant implants for up to 4 years.

Assessment of the skeletal health of healthy Nigerian men and women using quantitative ultrasound

The dietary intake of calcium by African populations, particularly in sub-Saharan Africa, is relatively low compared to the recommended intake for US adults. However, the rate of osteoporotic fractures in West African women is reported to be less than that for Caucasian populations. Because there is little published data regarding the skeletal status of African men and women, we used quantitative ultrasound (QUS) to assess the bone density of 435 Nigerian women and 321 Nigerian men between 16 and 89 years of age. A progressive decline in bone quality was observed beginning at about 40 years of age for both men and women. The mean stiffness index (SI) for the women between 20 and 35 years of age (n = 186) in this study was 102 +/- 17. The equation that best described the age versus SI relationship for women was SI = 79.7 + 1.887 (age) + -0.043 (age)2 + 0.00020 (age)3. For Nigerian men, the peak SI of 115 +/- 17 was seen in the 20- to 29-year-old age group. For men, the SI values remained above 100 until about age 60 years when a significant decline in SI was then observed. The best-fit curve of SI versus age for men was SI = 134.9 - 1.27 (age) + 0.019 (age)2 - 0.00014 (age)3. The broadband ultrasound attenuation (BUA), speed of sound (SOS), and SI values for the Nigerian men and women were comparable to or higher than those reported for Caucasian and Asian populations. These data should serve as reference values for adult men and women in sub-Saharan Africa.